The .40 truly does match the power level of the mil-spec .45. So why the major shift in the LE market back to the 9mm from .40?
Several reasons. A. 9mm power/performance has improved enough that the hi-end 9mm load now equals the .40. B. Most LEOs can't shoot as is evidenced by a couple decades now of shoot result analysis showing the bad guys don't drop at fewer shots with the .40 vs. improved 9mms, so C. Why not go back to the 9mm with practice ammo 1/2 price of .40 that is easier for the non-gun enthusiast typical LEO to learn on and have some confidence in and reserve the power 9mms for duty use? and, D. If the LEO IS a good shot under pressure, then the 9mm is now enough gun.
So, not quite what you ask, but unless there is a compelling reason for a Blue Label .40 (like much lower $$ than a 9mm, or you have a low/no cost supply source for .40 ammo), consider the 9mm instead. 1. Way cheaper to shoot with promo target-grade ammo available most anywhere (roughly 1/2 the cost of .40) 2. With way more costly Hi-Performance 9mm +P, the power equal of the .40/.45 as a duty/carry load and a couple more in the gun vs. .40.
PS. Lots of .40 police trade ins on the market as agencies swap back to 9mms...all it usually takes to change a Glock .40 to 9mm is a conversion barrel and a 9mm magazine...side result is .40/9mm conversion barrels are more and more "Out-of-stock--Back ordered".
R.